// Copyright 2007-2010 Baptiste Lepilleur and The JsonCpp Authors
// Distributed under MIT license, or public domain if desired and
// recognized in your jurisdiction.
// See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE

#ifndef NIM_CPP_WRAPPER_UTIL_JSON_READER_H_INCLUDED
#define NIM_CPP_WRAPPER_UTIL_JSON_READER_H_INCLUDED

#if !defined(JSON_IS_AMALGAMATION)
#include "json_features.h"
#include "value.h"
#endif  // if !defined(JSON_IS_AMALGAMATION)
#include <deque>
#include <iosfwd>
#include <istream>
#include <stack>
#include <string>

// Disable warning C4251: <data member>: <type> needs to have dll-interface to
// be used by...
#if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)
#pragma warning(push)
#pragma warning(disable : 4251)
#endif  // if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)

#pragma pack(push, 8)

namespace nim_cpp_wrapper_util {
namespace Json {

/** \brief Unserialize a <a HREF="http://www.json.org">JSON</a> document into a
 * Value.
 *
 * \deprecated Use CharReader and CharReaderBuilder.
 */

class JSON_API Reader {
public:
    using Char = char;
    using Location = const Char*;

    /** \brief An error tagged with where in the JSON text it was encountered.
     *
     * The offsets give the [start, limit) range of bytes within the text. Note
     * that this is bytes, not codepoints.
     */
    struct StructuredError {
        ptrdiff_t offset_start;
        ptrdiff_t offset_limit;
        String message;
    };

    /** \brief Constructs a Reader allowing all features for parsing.
     */
    Reader();

    /** \brief Constructs a Reader allowing the specified feature set for parsing.
     */
    Reader(const Features& features);

    /** \brief Read a Value from a <a HREF="http://www.json.org">JSON</a>
     * document.
     *
     * \param      document        UTF-8 encoded string containing the document
     *                             to read.
     * \param[out] root            Contains the root value of the document if it
     *                             was successfully parsed.
     * \param      collectComments \c true to collect comment and allow writing
     *                             them back during serialization, \c false to
     *                             discard comments.  This parameter is ignored
     *                             if Features::allowComments_ is \c false.
     * \return \c true if the document was successfully parsed, \c false if an
     * error occurred.
     */
    bool parse(const std::string& document, Value& root, bool collectComments = true);

    /** \brief Read a Value from a <a HREF="http://www.json.org">JSON</a>
     * document.
     *
     * \param      beginDoc        Pointer on the beginning of the UTF-8 encoded
     *                             string of the document to read.
     * \param      endDoc          Pointer on the end of the UTF-8 encoded string
     *                             of the document to read.  Must be >= beginDoc.
     * \param[out] root            Contains the root value of the document if it
     *                             was successfully parsed.
     * \param      collectComments \c true to collect comment and allow writing
     *                             them back during serialization, \c false to
     *                             discard comments.  This parameter is ignored
     *                             if Features::allowComments_ is \c false.
     * \return \c true if the document was successfully parsed, \c false if an
     * error occurred.
     */
    bool parse(const char* beginDoc, const char* endDoc, Value& root, bool collectComments = true);

    /// \brief Parse from input stream.
    /// \see nim_cpp_wrapper_util::Json::operator>>(std::istream&, nim_cpp_wrapper_util::Json::Value&).
    bool parse(IStream& is, Value& root, bool collectComments = true);

    /** \brief Returns a user friendly string that list errors in the parsed
     * document.
     *
     * \return Formatted error message with the list of errors with their
     * location in the parsed document. An empty string is returned if no error
     * occurred during parsing.
     * \deprecated Use getFormattedErrorMessages() instead (typo fix).
     */
    String getFormatedErrorMessages() const;

    /** \brief Returns a user friendly string that list errors in the parsed
     * document.
     *
     * \return Formatted error message with the list of errors with their
     * location in the parsed document. An empty string is returned if no error
     * occurred during parsing.
     */
    String getFormattedErrorMessages() const;

    /** \brief Returns a vector of structured errors encountered while parsing.
     *
     * \return A (possibly empty) vector of StructuredError objects. Currently
     * only one error can be returned, but the caller should tolerate multiple
     * errors.  This can occur if the parser recovers from a non-fatal parse
     * error and then encounters additional errors.
     */
    std::vector<StructuredError> getStructuredErrors() const;

    /** \brief Add a semantic error message.
     *
     * \param value   JSON Value location associated with the error
     * \param message The error message.
     * \return \c true if the error was successfully added, \c false if the Value
     * offset exceeds the document size.
     */
    bool pushError(const Value& value, const String& message);

    /** \brief Add a semantic error message with extra context.
     *
     * \param value   JSON Value location associated with the error
     * \param message The error message.
     * \param extra   Additional JSON Value location to contextualize the error
     * \return \c true if the error was successfully added, \c false if either
     * Value offset exceeds the document size.
     */
    bool pushError(const Value& value, const String& message, const Value& extra);

    /** \brief Return whether there are any errors.
     *
     * \return \c true if there are no errors to report \c false if errors have
     * occurred.
     */
    bool good() const;

private:
    enum TokenType {
        tokenEndOfStream = 0,
        tokenObjectBegin,
        tokenObjectEnd,
        tokenArrayBegin,
        tokenArrayEnd,
        tokenString,
        tokenNumber,
        tokenTrue,
        tokenFalse,
        tokenNull,
        tokenArraySeparator,
        tokenMemberSeparator,
        tokenComment,
        tokenError
    };

    class Token {
    public:
        TokenType type_;
        Location start_;
        Location end_;
    };

    class ErrorInfo {
    public:
        Token token_;
        String message_;
        Location extra_;
    };

    using Errors = std::deque<ErrorInfo>;

    bool readToken(Token& token);
    void skipSpaces();
    bool match(const Char* pattern, int patternLength);
    bool readComment();
    bool readCStyleComment();
    bool readCppStyleComment();
    bool readString();
    void readNumber();
    bool readValue();
    bool readObject(Token& token);
    bool readArray(Token& token);
    bool decodeNumber(Token& token);
    bool decodeNumber(Token& token, Value& decoded);
    bool decodeString(Token& token);
    bool decodeString(Token& token, String& decoded);
    bool decodeDouble(Token& token);
    bool decodeDouble(Token& token, Value& decoded);
    bool decodeUnicodeCodePoint(Token& token, Location& current, Location end, unsigned int& unicode);
    bool decodeUnicodeEscapeSequence(Token& token, Location& current, Location end, unsigned int& unicode);
    bool addError(const String& message, Token& token, Location extra = nullptr);
    bool recoverFromError(TokenType skipUntilToken);
    bool addErrorAndRecover(const String& message, Token& token, TokenType skipUntilToken);
    void skipUntilSpace();
    Value& currentValue();
    Char getNextChar();
    void getLocationLineAndColumn(Location location, int& line, int& column) const;
    String getLocationLineAndColumn(Location location) const;
    void addComment(Location begin, Location end, CommentPlacement placement);
    void skipCommentTokens(Token& token);

    static bool containsNewLine(Location begin, Location end);
    static String normalizeEOL(Location begin, Location end);

    using Nodes = std::stack<Value*>;
    Nodes nodes_;
    Errors errors_;
    String document_;
    Location begin_{};
    Location end_{};
    Location current_{};
    Location lastValueEnd_{};
    Value* lastValue_{};
    String commentsBefore_;
    Features features_;
    bool collectComments_{};
};  // Reader

/** Interface for reading JSON from a char array.
 */
class JSON_API CharReader {
public:
    virtual ~CharReader() = default;
    /** \brief Read a Value from a <a HREF="http://www.json.org">JSON</a>
     * document. The document must be a UTF-8 encoded string containing the
     * document to read.
     *
     * \param      beginDoc Pointer on the beginning of the UTF-8 encoded string
     *                      of the document to read.
     * \param      endDoc   Pointer on the end of the UTF-8 encoded string of the
     *                      document to read. Must be >= beginDoc.
     * \param[out] root     Contains the root value of the document if it was
     *                      successfully parsed.
     * \param[out] errs     Formatted error messages (if not NULL) a user
     *                      friendly string that lists errors in the parsed
     *                      document.
     * \return \c true if the document was successfully parsed, \c false if an
     * error occurred.
     */
    virtual bool parse(char const* beginDoc, char const* endDoc, Value* root, String* errs) = 0;

    class JSON_API Factory {
    public:
        virtual ~Factory() = default;
        /** \brief Allocate a CharReader via operator new().
         * \throw std::exception if something goes wrong (e.g. invalid settings)
         */
        virtual CharReader* newCharReader() const = 0;
    };  // Factory
};      // CharReader

/** \brief Build a CharReader implementation.
 *
 * Usage:
 *   \code
 *   using namespace Json;
 *   CharReaderBuilder builder;
 *   builder["collectComments"] = false;
 *   Value value;
 *   String errs;
 *   bool ok = parseFromStream(builder, std::cin, &value, &errs);
 *   \endcode
 */
class JSON_API CharReaderBuilder : public CharReader::Factory {
public:
    // Note: We use a nim_cpp_wrapper_util::Json::Value so that we can add data-members to this class
    // without a major version bump.
    /** Configuration of this builder.
     * These are case-sensitive.
     * Available settings (case-sensitive):
     * - `"collectComments": false or true`
     *   - true to collect comment and allow writing them back during
     *     serialization, false to discard comments.  This parameter is ignored
     *     if allowComments is false.
     * - `"allowComments": false or true`
     *   - true if comments are allowed.
     * - `"allowTrailingCommas": false or true`
     *   - true if trailing commas in objects and arrays are allowed.
     * - `"strictRoot": false or true`
     *   - true if root must be either an array or an object value
     * - `"allowDroppedNullPlaceholders": false or true`
     *   - true if dropped null placeholders are allowed. (See
     *     StreamWriterBuilder.)
     * - `"allowNumericKeys": false or true`
     *   - true if numeric object keys are allowed.
     * - `"allowSingleQuotes": false or true`
     *   - true if '' are allowed for strings (both keys and values)
     * - `"stackLimit": integer`
     *   - Exceeding stackLimit (recursive depth of `readValue()`) will cause an
     *     exception.
     *   - This is a security issue (seg-faults caused by deeply nested JSON), so
     *     the default is low.
     * - `"failIfExtra": false or true`
     *   - If true, `parse()` returns false when extra non-whitespace trails the
     *     JSON value in the input string.
     * - `"rejectDupKeys": false or true`
     *   - If true, `parse()` returns false when a key is duplicated within an
     *     object.
     * - `"allowSpecialFloats": false or true`
     *   - If true, special float values (NaNs and infinities) are allowed and
     *     their values are lossfree restorable.
     *
     * You can examine 'settings_` yourself to see the defaults. You can also
     * write and read them just like any JSON Value.
     * \sa setDefaults()
     */
    nim_cpp_wrapper_util::Json::Value settings_;

    CharReaderBuilder();
    ~CharReaderBuilder() override;

    CharReader* newCharReader() const override;

    /** \return true if 'settings' are legal and consistent;
     *   otherwise, indicate bad settings via 'invalid'.
     */
    bool validate(nim_cpp_wrapper_util::Json::Value* invalid) const;

    /** A simple way to update a specific setting.
     */
    Value& operator[](const String& key);

    /** Called by ctor, but you can use this to reset settings_.
     * \pre 'settings' != NULL (but nim_cpp_wrapper_util::Json::null is fine)
     * \remark Defaults:
     * \snippet src/lib_json/json_reader.cpp CharReaderBuilderDefaults
     */
    static void setDefaults(nim_cpp_wrapper_util::Json::Value* settings);
    /** Same as old Features::strictMode().
     * \pre 'settings' != NULL (but nim_cpp_wrapper_util::Json::null is fine)
     * \remark Defaults:
     * \snippet src/lib_json/json_reader.cpp CharReaderBuilderStrictMode
     */
    static void strictMode(nim_cpp_wrapper_util::Json::Value* settings);
};

/** Consume entire stream and use its begin/end.
 * Someday we might have a real StreamReader, but for now this
 * is convenient.
 */
bool JSON_API parseFromStream(CharReader::Factory const&, IStream&, Value* root, String* errs);

/** \brief Read from 'sin' into 'root'.
 *
 * Always keep comments from the input JSON.
 *
 * This can be used to read a file into a particular sub-object.
 * For example:
 *   \code
 *   nim_cpp_wrapper_util::Json::Value root;
 *   cin >> root["dir"]["file"];
 *   cout << root;
 *   \endcode
 * Result:
 * \verbatim
 * {
 * "dir": {
 *    "file": {
 *    // The input stream JSON would be nested here.
 *    }
 * }
 * }
 * \endverbatim
 * \throw std::exception on parse error.
 * \see nim_cpp_wrapper_util::Json::operator<<()
 */
JSON_API IStream& operator>>(IStream&, Value&);

}  // namespace Json
}  // namespace nim_cpp_wrapper_util

#pragma pack(pop)

#if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)
#pragma warning(pop)
#endif  // if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)

#endif  // JSON_READER_H_INCLUDED
